The present invention relates to the production of sound-producing polyurethane balls and relates more particularly to the production of a ball made from polyurethane through a foaming process with an audible sound-producing means fastened therein for producing sounds upon playing with the ball.
Several rubber and plastic materials are known to be suitable for use in making toy balls. In using a foamed polyurethane for the production of a toy ball, it is difficult to arrange a sound generator inside the toy ball. If a sound generator is fastened inside a toy ball, a sound hole must be provided for transmitting sounds to the outside. The present invention has been accomplished to provide a polyurethane ball with a sound generating means. In the production of a polyurethane ball according to the present invention, a column is fastened in the mold to block the sound hole on an extended socket of a speaker of a sound generating circuit. After the foaming process, an elongated hole is formed in the polyurethane ball thus obtained for transmitting sounds from the speaker to the outside. A spring switch is used in controlling the operation of the sound generating circuit so as to minimize the consumption of electric power.